From owner-freebsd-net Fri Feb 1 10:15:13 2002 Delivered-To: freebsd-net@freebsd.org Received: from avocet.prod.itd.earthlink.net (avocet.mail.pas.earthlink.net [207.217.120.50]) by hub.freebsd.org (Postfix) with ESMTP id 0261D37B422; Fri, 1 Feb 2002 10:13:54 -0800 (PST) Received: from user-2ivfov0.dialup.mindspring.com ([165.247.227.224] helo=gohan.cjclark.org) by avocet.prod.itd.earthlink.net with esmtp (Exim 3.33 #1) id 16WiC7-0005BU-00; Fri, 01 Feb 2002 10:13:52 -0800 Received: (from cjc@localhost) by gohan.cjclark.org (8.11.6/8.11.1) id g11Hl3H68287; Fri, 1 Feb 2002 09:47:03 -0800 (PST) (envelope-from cjc) Date: Fri, 1 Feb 2002 09:47:02 -0800 From: "Crist J. Clark" To: Alexey Luckyanchikov Cc: freebsd-stable@FreeBSD.ORG, freebsd-net@FreeBSD.ORG Subject: Re: Weird path MTU autodiscovery problem in 4.5-RELEASE Message-ID: <20020201094702.P152@gohan.cjclark.org> Reply-To: cjclark@alum.mit.edu References: <20020201125326.GA3036@alkar.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20020201125326.GA3036@alkar.net>; from alexl@alkar.net on Fri, Feb 01, 2002 at 02:53:26PM +0200 X-URL: http://people.freebsd.org/~cjc/ Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Fri, Feb 01, 2002 at 02:53:26PM +0200, Alexey Luckyanchikov wrote: > Hello, > > I have such network topology: > > +--------+ +--------+ +--------+ > | Server |<---- MTU 1500 ---->| Router |<---- MTU 1476 ---->| Client | > +--------+ +--------+ +--------+ [snip] > 14:06:48.682558 router > server: icmp: client unreachable - need to frag (mtu 1476) for server.7 > client.1371: [|tcp] (DF) (ttl 61, id 25428, len 1500) (ttl 253, id 2491, len 56) > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > Router say to server that he must to decrease packet size Is "router" the same IP address that "server" has as the route to "client?" That is, there aren't any aliases on "router's" interface with "server" making problems? -- Crist J. Clark | cjclark@alum.mit.edu | cjclark@jhu.edu http://people.freebsd.org/~cjc/ | cjc@freebsd.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message